Many known antimicrobial topical compositions are designed for treatment of existing wounds or skin disorders, and are not used as barriers to future infectious contact. These topical agents penetrate the wound or infected area, and deliver the antimicrobial compound to the site of the contamination. Many of these commercially available topical formulations consist of an oil based carrier such as petrolatum or liquid paraffin which is insoluble or nearly insoluble in water, plus a bioactive agent. Such compositions tend to be greasy, tacky, stain causing, and may be difficult to remove. Specific topical bioactive skin ointments used to treat infections are described, for example, in Edwards U.S. Pat. No. 4,803,066, issued Feb. 7, 1989, and Holtshousen U.S. Pat. No. 4,671,957, issued Jun. 9, 1987.
Other antimicrobial surface-coating compositions have been formulated for the coating of substrates such as wood, metal, textile, thread, canvas, carpeting, paper and masonry. Most of these compounds are long lasting, toxic, irritating to skin, and not easily removable. Many are formulated to provide a semipermanent polymer coating. Ona et al. U.S. Pat. No. 4,614,675, issued Sep. 30, 1986, and Baldwin U.S. Pat. No. 4,467,013, issued Aug. 21, 1984, describe an antimicrobic used to treat fibers, fiber-containing material and non-woven fabrics. Mustacich et al. U.S. Pat. Nos. 4,479,795 and 4,343,788 describe a carboxylate antimicrobial agent releasably incorporated into permeable polymers. Young et al. U.S. Pat. No. 4,500,338, issued Feb. 19, 1985, discloses a hydrolyzable organic titanium compound containing a microbiocide and an optional organopolysiloxane for use as a surface disinfectant.
Other prior art has focused on the incorporation of an antimicrobial agent into surface coating substances such as paints or varnishes to prevent the decomposition of the surface coating. Deinet et al. U.S. Pat. No. 4,448,906, issued May 15, 1984, Dandt et al. U.S. Pat. No. 4,404,196, issued Sep. 13, 1983, Sidi et al. U.S. Pat. Nos. 4,022,906, issued May 10, 1977, 4,012,261, issued Mar. 15, 1977, 3,962,271, issued Jun. 8, 1976, 3,952,000, issued Apr. 20, 1976, 3,890,264, issued Jun. 17, 1975, and Minieri U.S. Pat. No. 3,929,705, issued Dec. 30, 1975 all describe such inventions.
In the field of protective hand creams, one composition marketed under the Invisible Glove trademark is made of about 60% water, 14% glycerin, 1% sodium silicate, and 25% soap (sodium laurate). This composition has been commercially successful as a cream applied prior to undertaking a task that involves exposing the hands to inks, grease, paints or the like. The cream dries to form a thin, slightly tacky film on the hands that repels contaminants. Mattson et al. U.S. Pat. No. 4,738,987 discloses a comparable skin care composition compounded as a dispersion of water with soap, a water-soluble alkali metal silicate, and sulfonated castor oil having a pH adjusted with acid to 6.5 to 10. See also Morgulis U.S. Pat. No. 2,698,824, issued Jan. 4, 1955, which describes a non-bioactive silicone-based ointment which provides a non water soluble protective layer on the skin.
These compositions tend to fall into one of several categories: compositions containing an antimicrobial designed for immediate use on the skin, compositions containing an antimicrobial and an agent such as a siloxane to provide extended substantivity on the skin, and compositions for temporary use (i.e., which wash off readily with soap and water) but which lack an antimicrobial. None are particularly suited for protecting health care workers. During surgery, doctors and health care workers are commonly exposed to the blood or other bodily fluids of the patient. Protective gowns, masks and gloves may not provide adequate protection of all exposed skin areas, and may hinder delicate operations. A need exists for a skin protectant composition that can be worn under of protective clothing and on skin which remains exposed, which composition minimizes the chance that a health care worker will contract AIDS or other infectious diseases. However, the composition should be readily removable when a procedure or operation is over so that the physician or health care worker can wash it off and remove any residual contamination. The present invention addresses this need.